Cellulosic composition of matter containing butyl propionate



Patented Jan. 12 1932 "Swifts" COMPANY, on nocHEsTEanEw YORK, A ooRPoRATIonor NEW YORK r cELLULosIc oo krrosi ron on MATTER CONTAINING BUTYL :enorIonATE Application fiieu' September '23, 1929; seriaino. 394,640.

This invention ii'elates to compositions of; matter in which cellulose acetate is combined-v or mixed with otherv substances, such as a compatible plasticizer, and a common Solvent for both, with or without other useful addition agents, so that the resulting product will have propertiessuch as will makethe ,com-

position highly advantageous for use in the plastic and analogousarts,*such; for instance,

as the manufacture of wrapping sheets,

photographic film, artificial silk, varnishes or lacquers, and the like. 1

One object of this invention is to produce a composition of matter which maybemade into permanently transparent, strong "and,

flexible sheets or films of desired thinness which are substantially waterproof,fare:unaflected by ordinary photographic fluids and possess the desired properties ofasupport 2o for sensitive photographic coatings. "Another object of my invention is to produce a' composition which. is capable of; easyand convenient manipulation in the plastic and analogous arts, such as in themanufacture' of sheets, films, artificial silk filaments, varnishes, lacquers and the like; and to. pro 7 duce a composition which will-not -injure, orbe injured by, the substances or surfaces with? which it is associated during. manufacture, storage or use. ;Other and further. objects will hereinafter become apparent to those skilled in the artto which this invention pertains w it in the various 'plastic arts it "is necessary to mix therewith such plasticizing or condi- :tioning agents as camphor, triphenyl phOS? A phate,j monochlornaphthalene or the like.

Certain of these and other addition agents-- are also added for the purpose; of-redu'c-ing the infiammability of the product.

inducing agents, such as the higher alcohols and their esters, are sometimes also added.

{Similarly addition compounds ofvarious kinds have beenemployed to increase'flexibility, transparency, toughness and otl1 erg properties which will enhance .the valueof the resulting product. "Addition products for the same or similar'purposes are 'also Plastic filaments, moulded coinpounds and the like. While the plasticizers er. other addition .,1,s41,311ff PATENT oFFic 15; STEWART :r. miinrtonn, or noo EsiTER;itn w xoizx, AssIe oalTo aismrullxoisxgk addedto celluloseacetate'toprepare p in thelother plastic arts, such as in the manuf facture .of lacquers, varnishes, artificial silk:

agentsheretofore discoveredhavehadtheir utility in the-art, the increasing USE-t0 which cellulose acetate has been put and the increase ingnumberof desirable properties required- 7 I of cellulose: acetate for mostpurposes has made the discovery of new and economical plasticizers or other addition agents a matter of considerableimportance to the art.

- I have discovered thatr'valuable properties may be induced in and /or contributed to compositions containing cellulose acetate by; add-Y ing thereto the plasticizingcompo'und 'butyl propionate in the'presence ofa solvent, such as acetone, which will dissolve both the cellui p is a liquid atordinaryatmospheric tempera; p j

lose acetate and plasticizer. This plasticizer ture and hasthe formula Y cacHicoooacacmca ot can;

It may, be either the normalbutyl orisobutyl propionatethat is. employed, either compound being a-successful, plasticizer and both.

being referred to hereinafiter as butyl pro-f pionate, It is particularly compatible with cellulose acetate in the percentages hereinaf ter. given.{ It is not anexpensive compound 7 and not parti'cularly' diflicult' to produce, or

obtain upon the openm'arket; Theparticu larly useful propertieswhieh induces in or contributes to a cellulosiccomposition con-' tainingfitare hereinafter enumerated;

In order that those skilled in this art may better understand my; invention, I would 'manufacture of photographic film or otherf 'sheetsmy' new composition. of matter maybe state, by" Way of illustration, that for the compounded. asfollows: 'partsi of ace-I tone-soluble. cellulose acetate i. e. cellulose acetate containing-from 36% to 42% acetyl radical,kapproximately, isv d ssolved with stirring at atmospheric temperature in 300to it being found preferable to employ approximately 80 parts thereof. Within the limits stated, the amount of plasticizer may be de creased or increased, depending upon wheth- 5 er it is desired to decrease or increase, respec 2 flexible as shown bytlre tact that it will withstand many folds upon a modified Schopper fold-tester (commonly used for such purposes)- without breaking and that even after being subjected for 65 days 'to air maintained at a temperature of 65 Q]. the film still maintains flexibility, demonstrating that the filnr will withstand ordinary usage satisfactorily for many years, whereas a film formed trom a mere solution of cellulose acetate in ace 3o tone or other similar solvent is brittle and fragile after subjected to'the; same treatment foras littlieas thirty days or even a lesser time. 7 The sum total. of the above advantageous properties of product produced from my newcomposition is considerefi-lulose propionate, butyrate and the like, or

with mixed organic and/or morgamc'esters,

ably in excess of that of products produced with what have previously been regarded as the better plasticizers.

Other similarso=lvents (instead of acetone) which are compatible with the cellulose acetate and my newpl astici-zer may alsooccu-r to those skilled in this" art: In like manner this plastioizer may be compounded with other si-ngle organic esters of cellulose, such as celsuch as cellulose aceto stearate, aceto-malate, or cellulose Introacetate, orwlth the cellu lose others, a su table solvent which will disboth the ce-llul'osi-c derivative-and the plasticizer being employed.

part of this application, clearly illustrates the particular advantages of employing my." novel plasticizerin the plastic arts. In this drawingthere are plotted lines or curves graphically depicting the properties of film produced froma com-position containing cellulose acetate and this plasticizer'. On the horizontalaxis is indicated the various percen-tagesofmy plasticizer that may be employed with the cellnlosrc acetate, this ercentage oelng given in parts'added to the cellulose acetate I'ELt'lIBI lZl IEtH parts of the composition; for instance, parts plasticizer added to 100- parts cellulose acetate is denoted as 30% plasticizer added. On the vertical axis at (a), on theleft, is indicated in percentage over the check sample the initial flexibility of a film which has been formed as described from my novel composition and which has been subjected to air at C. for 24 hours to free it of solvent; the rate of combustionof that film is also indicated by this same column (a) at (b) on the right is indicated the length of time in days that the film will maintain flexibility when subjected to air kept at a temperature of C. The curve (A) de- 7 picts initial flexibility of the film, the curve (B) depicts the ability of the: film. to maintain flexibility and the curve (C) depicts the rate: ofcombustion ofthe film-all with various' percentages of my novel plasticizer and all as compared to the respective properties of a film produced from a solution of cellulose acetate in acetone and a hypothetical inert-material substituted for the plasticizer as denoted by curve indicating unity of 10 0% and 30 days for (a') and (b) It will thus: be noted "that'my novel plasticizer has the faculty of giving, to a product produced therefiom: very good initial flexibility and a low combustion rate, and that the product maintains its flexibility quite 'well. The preterred percentage of my plasticizer which is desirable to employ to contribute any particular property to the final product will be obvious from an inspectionof this drawing; the best percentage to em.- p'loy will depend upon which property it is desired to feature most in the final product.

Inasmuch as my above described composition of matter is quite useful inthe production of films and sheets it will be apparent that my new plasticizer may also be employed with advantage in the other branches of the plastic art. For instance, my above described composition of-matter may be employed in the manufacture of artificial silk by the dry spinning method. With the proper coagulating bath it may also be employed for wet spinning. It may be desired to employ a composition of diflerent viscosity or evaporation characteristics but this is a mere matter of changing the solvent proportion or The accompanying drawing, forming a adding evaporation retardants such as triacetin or other'high or intermediate boiling constituents, as has been well known in the art for more than a'decade. My novel plasticizer may also be employed with advantage in connection with a number of the known lacquer and varnish formulae -with which it may be found to be compatible. In such cases the plasticizer is usually first put into solution with the cellulose acetate solution and if non-solvents are added for the precipitate the cellulose acetate from solu- 'tion. Other uses Within-the scope of my invention will also suggest themselves to those skilled in the art.

What I claim as my invention, and desire to be secured by LettersPatent of the United States,is:- Y i f. v

' 1. composition of matter Comprising Signed at Rochester, New York this, 19th day of September, 1929. V STEWARTJ. CARROLL, 

